Shellfish Corbicubicula sumatrana and Contradens contradens are benthic animals inhabiting in muddy and sandy water bottom. The nature of these benthic animals tend to settle down and have a very low level of mobility. Besides, the shells also are filter feeder . Two types of these shellfishes is commonly found in Lake Singkarak. Around the lake there are areas of agriculture and some of the rivers that flow into the lake. Seeing by high agricultural activities around the lake worried that the effects of excessive pesticide used will be accumulated on water. Research aimed to determine pesticide compounds that accumulated in aquatic biota of Lake Singkarak especially Corbicula sumatrana and Contradens contradens. This research had been done from February to July 2015. Samples were taken at the mouth of Sungai Batang Lembang a river that flow into Lake Singkarak. Accumulation analysis using Gas Chromatography onto meat extract of these two shellfishes. The result shows that the Corbicula sumatrana’s meat contains 50 chemical compounds and the Contradens contradens’s meat discovered 55 types of chemical compounds as well as on the gills Contradens contradens found 137 chemical compounds. Ten derivative DDT of all 137 chemical compounds which found.